Myntra.com — refund amount less

Address: Bangalore, Karnataka

Amount paid for a product was rs 622 for which break up was as follows:
Bag amount: rs 999
Bag discount: rs 400
Total: rs 599
Shipping charges: rs 149
Coupon discount: rs 149
Total: rs 599
Tax: rs 23
Total: rs 622

On return of product since product was not in stock for exchange amount received was rs 473.
Amount to be refunded should have been either rs 622 or rs 599. How come amount is rs 473.
As per the shared 2 screenshots of the original invoice
And the invoice for return conveniently the discount amount has been changed and a refund has been given.